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排序方式: 共有7847条查询结果,搜索用时 15 毫秒
61.
June A Peters Susan T Vadaparampil Joan Kramer Richard P Moser Lori Jo Peterson Court Jennifer Loud Mark H Greene 《Genetics in medicine》2006,8(12):760-770
PURPOSE: This study is part of an ongoing National Cancer Institute multidisciplinary, etiologically-focused, cross-sectional study of Familial Testicular Cancer (FTC). The current report targets interest in clinical genetic testing for susceptibility to FTC. METHODS: Demographics, knowledge, health beliefs, and psychological and social factors were evaluated as covariates related to interest in genetic testing. RESULTS: The majority (66%) of 229 participants (64 affected men, 66 unaffected men, and 99 women) from 47 multiple-case FTC families expressed interest in having a genetic test within 6 months, should such a test become available. Interest was similar among the three subgroups mentioned above. Worries about insurance discrimination based on genetic test results were associated with a significantly lower interest in testing. Alternatively, participants were more likely to be interested in genetic testing if they were younger and had higher levels of family support, a physician's recommendation supporting testing, cancer distress, and a need for information to inform the health care of their children. CONCLUSIONS: This study reveals social and relationship factors that FTC survivors and their relatives considered important when contemplating the use of new genetic technologies. This is the first study describing hypothetical interest in genetic testing for familial testicular cancer. 相似文献
62.
63.
Promotion of bone formation by simvastatin in polyethylene particle-induced osteolysis 总被引:10,自引:0,他引:10
von Knoch F Wedemeyer C Heckelei A Saxler G Hilken G Brankamp J Sterner T Landgraeber S Henschke F Löer F von Knoch M 《Biomaterials》2005,26(29):5783-5789
The effects of statins on bone formation in periprosthetic osteolysis have not been determined to date. We investigated the effect of the HMG-CoA reductase inhibitor simvastatin on osteoblastic bone formation under conditions of ultra-high molecular weight polyethylene (UHMWPE) particle-induced osteolysis. The murine calvarial osteolysis model was utilized in 21 C57BL/J6 mice randomized to three groups. Group I underwent sham surgery only, group II received UHMWPE particles, and group III, particles and simvastatin treatment. After 2 weeks, calvaria were processed for histomorphometry and stained with Giemsa dye. New bone formation was measured as osteoid tissue area within the midline suture. Bone thickness was quantified as indicator of net bone growth. Statistical analysis was performed using one-way ANOVA and a Student's t-test. New bone formation and bone thickness were significantly enhanced following simvastatin treatment. New bone formation was 0.008+/-0.008 mm2 in sham controls (group I), 0.015+/-0.012 mm2 after particle implantation without further intervention (group II), compared to 0.083+/-0.021 mm2 with particle implantation and simvastatin treatment (group III) (p=0.003). The bone thickness was 0.213+/-0.007 mm in group I, 0.183+/-0.005 mm in group II, and 0.238+/-0.009 mm in group III (p=0.00008). In conclusion, simvastatin treatment markedly promoted bone formation and net bone growth in UHMWPE particle-induced osteolysis in a murine calvarial model. These new findings indicate that simvastatin may have favorable osteoanabolic effects on wear debris-mediated osteolysis after total joint arthroplasty, involving local stimulation of osteoblastic bone formation. 相似文献
64.
Placental inflammation and perinatal transmission of HIV-1 总被引:2,自引:0,他引:2
Mwanyumba F Gaillard P Inion I Verhofstede C Claeys P Chohan V Vansteelandt S Mandaliya K Praet M Temmerman M 《Journal of acquired immune deficiency syndromes (1999)》2002,29(3):262-269
The effect of placental membrane inflammation on mother-to-child transmission (MTCT) of HIV-1 is reported. Placentas from HIV-1-infected women were examined as part of a perinatal HIV-1 project in Mombasa, Kenya. Polymerase chain reaction analysis was used to test for HIV-1 in the infants at birth and at 6 weeks. The maternal HIV-1 seroprevalence was 13.3% (298 of 2,235). The overall rate of MTCT of HIV-1 was 25.4%; polymerase chain reaction analysis revealed that of the 201 infants 6.0% (12) were already HIV-1-positive at birth (intrauterine transmission) and 19.4% (39) were infected during the peripartum period or in early neonatal life (perinatal transmission). The prevalence of acute chorioamnionitis was 8.8%, that of deciduitis was 10.8%, and that of villitis was 1.6%. Acute chorioamnionitis was independently associated with peripartum HIV-1 transmission but not with in utero MTCT (17.9% vs. 6.7%, respectively; adjusted odds ratio, 3.9; 95% confidence interval, 1.2-12.5; p =.025). Other correlates of perinatal MTCT were presence of HIV in the genital tract and in the baby's oral cavity and a high maternal viral load in peripheral blood. The adjusted population attributable fraction of 12.8% (95% confidence interval, 1.5%-22.8%) indicated that approximately 3% of MTCT could be prevented if acute chorioamnionitis was eliminated. We suggest that further research on the role of antimicrobial treatment in the prevention of chorioamnionitis and the reduction of peripartum MTCT needs to be performed. 相似文献
65.
Christopher L. King Robert J. Stupi Nancy Craighead Carl H. June George Thyphronitis 《European journal of immunology》1995,25(2):587-595
Ligation of CD28 provides a costimulatory signal to T cells necessary for their activation resulting in increased interleukin (IL)-2 production in vitro, but its role in IL-4 and other cytokine production and functional differentiation of T helper (Th) cells remains uncertain. We studied the pattern of cytokine production by highly purified human adult and neonatal CD4+ T cells activated with anti-CD3, phorbol 12-myristate 13-acetate (PMA) and ionomycin, or phytohemagglutinin (PHA) in the presence or absence of anti-CD28 in repetitive stimulation-rest cycles. Initial stimulation of CD4+ cells with anti-CD3 (or the mitogens PHA or PMA+ionomycin) and anti-CD28 monoclonal antibodies induced IL-4, IL-5 and interferon-γ (IFN-γ) production and augmented IL-2 production (6- to 11-fold) compared to cells stimulated with anti-CD3 or mitogen alone. The anti-CD28-induced cytokine production corresponded with augmented IL-4 and IL-5 mRNA levels suggesting increased gene expression and/or mRNA stabilization. Most striking, however, was the progressively enhanced IL-4 and IL-5 production and diminished IL-2 and IFN-γ production with repetitive consecutive cycles of CD28 stimulation. The enhanced Th2-like response correlated with an increased frequency of IL-4-secreting cells; up to 70% of the cells produced IL-4 on the third round of stimulation compared to only 5% after the first stimulation as determined by ELISPOT. CD28 activation also promoted a Th2 response in naive neonatal CD4+ cells, indicating that Th cells are induced to express a Th2 response rather than preferential expansion of already established Th2-type cells. This CD28-mediated response was IL-4 independent, since enhanced IL-5 production with repetitive stimulation cycles was not affected in the presence of neutralizing anti-IL-4 antibodies. These results indicate that CD28 activation may play an important role in the differentiation of the Th2 subset in humans. 相似文献
66.
Hepatitis C infection among injecting drug users in general practice: a cluster randomised controlled trial of clinical guidelines'' implementation 下载免费PDF全文
Walter Cullen June Stanley Deirdre Langton Yvonne Kelly Anthony Staines Gerard Bury 《The British journal of general practice》2006,56(532):848-856
BACKGROUND: Hepatitis C is a common infection among injecting drug users and has important implications for general practice. Although several clinical guidelines concerning the infection have been published, their effectiveness has yet to be tested. AIM: To assess the effectiveness of a general practice-based complex intervention to support the implementation of clinical guidelines for hepatitis C management among current or former drug users attending general practice. DESIGN OF STUDY: Cluster randomised controlled trial. SETTING: General practices in the Eastern Regional Health Authority area of Ireland. METHOD: Twenty-six practices were randomly allocated within strata to receive the intervention under study or to provide care as usual for a period of 6 months. There was screening for patients attending general practice for methadone maintenance treatment for hepatitis C and referral of anti-HCV antibody positive patients to a specialist hepatology department for assessment. RESULTS: At study completion, patients in the intervention group were significantly more likely to have been screened for hepatitis C than those in the control group, odds ratio adjusted for clustering 3.76 (95% confidence interval [CI] = 1.3 to 11.3) and this association remained significant after adjusting for other potentially confounding variables, using multiple logistic regression, with the odds ratio adjusted for clustering 4.53 (95% CI = 1.39 to 14.78). Although anti-HCV antibody positive patients in the intervention group were more likely to have been referred to a hepatology clinic, this was not statistically significant (P = 0.06). CONCLUSION: General practice has an important role in the care of people at risk of hepatitis C and when appropriately supported can effectively implement current best practice. 相似文献
67.
We investigated the effect of beta-adrenergic stimulation on the heart rate and QT interval in syncope children with or without coexisting ventricular arrhythmias (VA). Of the 24 children who presented with syncope or presyncope and showed negative tilt test, 13 were classified into a group with VA and the remaining 11 without VA. The provocative test was performed in bolus infusion and continuous infusion. RR, QT, and QTc intervals on routine 12-lead surface electrocardiogram were obtained during each stage of isoproterenol infusion. In all cases, malignant ventricular arrhythmia and syncope were not induced by isoproterenol provocative test. RR and QT intervals were shortened and QTc intervals were prolonged as the isoproterenol dose was increased in both groups and methods. The QTc interval reached its peak level after the bolus injection of 1.0 microgram and during the continuous infusion of 0.03 microgram/kg/min. The two groups showed no significant difference in the QTc interval change according to the infusion methods. This study indicates that changes in the heart rate and QT interval by beta-adrenergic stimulation were not different according to the coexisting ventricular arrhythmias in syncope children with negative head-up tilt test. 相似文献
68.
Subunit interaction with PICK and GRIP controls Ca2+ permeability of AMPARs at cerebellar synapses 总被引:2,自引:0,他引:2
At many excitatory central synapses, activity produces a lasting change in the synaptic response by modifying postsynaptic AMPA receptors (AMPARs). Although much is known about proteins involved in the trafficking of Ca2+-impermeable (GluR2-containing) AMPARs, little is known about protein partners that regulate subunit trafficking and plasticity of Ca2+-permeable (GluR2-lacking) AMPARs. At cerebellar parallel fiber-stellate cell synapses, activity triggers a novel type of plasticity: Ca2+ influx through GluR2-lacking synaptic AMPARs drives incorporation of GluR2-containing AMPARs, generating rapid, lasting changes in excitatory postsynaptic current properties. Here we examine how glutamate receptor interacting protein (GRIP, also known as AMPAR binding protein or ABP) and protein interacting with C-kinase-1 (PICK) regulate subunit trafficking and plasticity. We find that repetitive synaptic activity triggers loss of synaptic GluR2-lacking AMPARs by selectively disrupting their interaction with GRIP and that PICK drives activity-dependent delivery of GluR2-containing receptors. This dynamic regulation of AMPARs provides a feedback mechanism for controlling Ca2+ permeability of synaptic receptors. 相似文献
69.
This study examined the influence of patient sex and clinician sex and sex role for a case, meeting minimum diagnostic criteria for Antisocial Personality Disorder, in which patient sex was varied. The purpose was to provide an in-depth evaluation of the process by which patient sex and characteristics of clinicians may contribute to bias in personality disorder diagnoses. Psychologists (N = 167) read two cases, including the target case, and provided symptom ratings and diagnoses. A sex-unspecified condition served as a baseline to assess for over- and underpathologizing bias, and diagnoses based on the symptom ratings were compared to assigned diagnoses. Clinician sex role was assessed using the Bem Sex Role Inventory-Short Form. Results revealed that bias occurred when the patient's sex (female) was inconsistent with the gender weighting of the symptoms in the case (masculine), but the direction of the bias was consistent with sex roles (underdiagnosis of sex-role-inconsistent diagnoses, overdiagnosis of sex-role-consistent diagnoses). Path models of over- and underdiagnostic bias were developed using structural equation modeling. Patient sex had a direct effect on diagnostic ratings whereas clinician sex role had an indirect effect through symptom ratings. 相似文献
70.
Wayne Kepron June M. James Bryan Kirk Alec H. Sehon Kam S. Tse 《The Journal of allergy and clinical immunology》1977,59(1):64-69
Immunization of neonatal dogs with a conjugate of 2,4-dinitrobenzene and ovalbumin (DNP2-OA), using aluminum hydroxide as the adjuvant, elicited long-lasting (over 30 wk) anti-DNP and anti-OA IgE antibody responses of high titers as determined by homologous passive cutaneous anaphylaxis. Low antigen doses of 10 or 50 μg were more effective than the higher doses of 250 or 1,250 μg in inducing high IgE antibody levels. However, this method of immunization failed to elicit any detectable IgE antibody response in adult dogs. Bronchoprovocation with antigen of sensitized animals having IgE antibody titers in excess of 64 resulted in a marked increase in airflow resistance, which could be corrected by the administration of nebulized isoproterenol. On the other hand, sensitized animals with IgE antibody titers in the order of 64 did not manifest significant bronchoconstriction on inhalation challenge but developed anaphylaxis following intravenous injection of the antigen. 相似文献